Range-finder.



P. G. NUTTlNG.' y

RANGE FINDER.

Arme/umm FILED MANI. |916.

Patented im 25,1%...

2 snszTs-SHEU 1.

Ano/wem P. G. NUTTING.

RANGE FINDER.

APPLICATION min MAval. 191e.

Patented June 25, 1918.

2 SHEETS-surft 2.

l/Vl/ENTR mgm " invention embodied in a gun-sight 'and PERLEY Gt.NUT'.lZIll'Cw,` 0F ROCHESTER, NEW YORK.

RANGE-FINDER.

Letonia,

lSpecification of Letters Patent.

Application filed May 31, 1916. Serial No. 100,847.

To all whom t may concern Be it known that I, PERLEY G'. NUTTING, ofRochester, in the county of Monroe and State of New York, have inventedcertain new and useful Improvements in Range- Finders; and I do herebydeclare the following to be a full, clear, and exact description of thesame, reference being had to the accompanying drawings, forming a partof this specification, and to the reference-numerals marked thereon.

My present invention relates to range finders or telemeters fordeterminingr the distance of an observed object from the point ofobservation, and itrelates more specifically to that class'in which anadjustable member is employed to obtain the coincidence or alinement oftwo normally noncoincident or unalined images of an observed object, thedisplacement of the adjustable member when the images are coincidentindicating on a scalev the `range of the object. One of the objects ofmy invention is to provide a simple instrument that will be bothoptically sensitive andmechani-` cally insensitive and which willltherefore enable the determination of the distance of` objects atdifferent ranges, to be made easily and accurately.` To these and otherends the invention resides in certain improvements and combinations ofpartsall as will be hereinafter more fully described, the novel featuresbeing pointed out in the claims at the end of the specification.

In the drawings:

Figure l is a side elevation of a range Ifinder constructed `inaccordance with andk illustrating one embodiment of my invention- Fig. 2is a longitudinal sectional view thereof; i

Fig. 3 is a cross sectional view on the line 3-3 of Fig. 2;

Fig. i is a Similar view on the limi-4 of' Fig. 2

Figl is 'a fragmentary longitudinal `de-2 tail sectional view .on thevline `5.---5 of Fig. 2;

Fig. 6 is a fragmentary detail .viewlof the under side of the tubeshowing the; scale for indicating the distance of an ob-` ject;` l 0 A..i p

Fig. 7 is a view showing `features of the range iinder, the same beingshown in side elevation; and

Patented lune 25, IFI@ Fig. 8 is a diagrammatic view showing the opticalsystem of Fig. 7. j Similar reference numerals throughout the severalfigures indicate the same parts.

In carrying out my invention in the present instance, I establish a baseline on the distance of separation of two substantially parallel mirrorsupon which separate images of the objects are viewed simultaneously froman angle of 45, one of the mirrors is semi-transparent so that the othermirror can `reflect the rays of its image through it and make possiblethe superpositioning of the images from a common viewpoint. As the angleofincidence ofrays` from the object is different on thetwo inir-` ror.surfaces, the images will 'not normally register but an adjustable orvariable optical element is utilized to correct the angle of one inaccordance `with that of the other resulting in the exact register ofthe two` images.` The said adjustable element cooperates `with a scaleand the reading on this scale after the registration of the images hasbeen edected is a true reading of the distance or range of the objectfrom the instrument. For very distant objects the adjustable element ismade more sensitive so that registration of the images can be, effectedwith greater ease and certainty.`

Referring more particularly to the drawings, 1 and 2 indicate a pair ofreflectors spaced from each other within a tube 3 and arranged inparallelism to each other at an angle of approximately 45 to the axis ofthe tube. Openings 4 are provided in one side of the tube adjacent thereflectors in order to admit relatively angular rays of light A, B fromthe object to the respective f reflectors. Assuming that the rays A arethe more direct rays from the image, that is, that theirpath is normaltothe axis-of s the tube 3, it follows that these rays will be directedby `the reiiector 1 down` the axis of the tube and along the axis of atelescope 5 which forms an extension ofthe tube and magnifies the sizeof the image produced by` the reflector from the point of observation` 2at a dierent angle and will be reflected through the tube atacorresponding divergence from the lineof the aXis thereof and of therays A after reflection, the angle and dVefgeHCe being gleaten with., a.near.. object. than with a far object.

It being required that the images castby both reflectors be viewablefrom the samepOnt. offobservatiorn' provide a simple ar! rangement forpermittingl the transmission of the rays B to the eye-piece `C and`itcon-V sists in Vmaking the reflector. 1, semi-trans-y parentbyincomple'tely silvering'the backv of a. mirrorA platev so.. thatx'itwill. both transmit and reflectlthefraysof light. The image.A formed..the rays" B reflected, at 2 passes ,thrtughft emir'rtr. ir and becomesvisibl'eiath'() together with therilnage formed bythelraysA reflectedatl, `fV 4 B-.Cllfe [0f the '2,I1g11l51.. direction. of, the rays B- and[their deflectionwithin the tube i 3f afterr reflection `atf`2rhereto,fore'.A `de.-

eexibeatheweieeeee 'eei'veved at, C Will. anneeileutOfa'egietei and.' a.double Qutlne er, the @eject will; be; 'Seemann pan of one; injiage,Aoverlapping', the other." The lack of,

. registerzjwill be ,more` pronounced if theolo-y jeetf is' 'neet thanfffargawey; eee.Heirlglyv as, Athelrelative.angle.lof. the ray. B`..is.greater'.v orlless, But.in,ether.finstance, registration of` the ,nwo,mges'-can be ,effected .by bending.l the ray]` or .raysB' back. .intoalinementfwitlr the,y airis of; the, tube 3 iand; with ,thefreected ray,A 'before'tlic, 'ray B reaches the. semitransparent.niirror1,y"1i`iirtlne13 by utilizing: an yadj ustable., element -fo,r..this lpurp ose )andy indicatinglte mevementeupen e, distance, sal.,- direct.readingV can obtained of; the, distance` from.` the; instrument. of( agiven objfle'accbdingly. asU the r'eltvefangle ofi rayslA and Bi,emanating.therefroinfrequire @greater or a lessmoveinent of theadjust.-vable. element .to straightenonelray into .alinev' Ident with theI other.after reflection within the., instrument.

` IntheL practice. oflny, invention, Iy prodnce cclncidence, of theimages by the emnleymellte'f e deeetins member E (Fie 8). which is`interpcsedin thejpath of theray, B. andis'movaqble laterally ofthe axisYof the tube". to Ibend said ray `until it., coincides in diictionwiththereflected rayA.Y Thedis-fV plaeement of the ilglgeinher,E. thenindicates tliadi'eteiies Oftheebieet len. el Seele. vDl In, the'',plse'iit, instance, the.; den'ectin'g {memberll Eire "ene'e, pair.ef.- fee'neetvely eerlv'ex and, concave, f lenses".` l(1f-fthe; saine.;focal i length, thatwqrk, 1;]cenjuncndn anbieten 1.

etherend nheh, Hermana eeeuny-einsinoa their, optical faires' lfin.alinernent 'with'f th et, ef. thefteleeeepe The. feeel Ilelaths of#'these le. Meeerdimted nithfhe 'distance i qfsepa non',Qtthenniymrsranda,andthe nef-t efneil: ef 'eemileileeties,.lefieee.viefeiael.' that@ e Wedeeetvefleelelengle.

The deviation produced by this pair of lenses is dependent upon twofactors: (1) the displacement from the coaxial position, and (2)V theequivalent focal length of each component. .Hence, the focal length ofeither lens determines and is proportional tothe sensibility of theinstrument, namely,

the displacement required to bring into cowhere f is the focal length ofthe lens F and M is the distance between the mirrors 1 and In practice,ff is so chose-n that; c is a distance conveniently measured on a screw(about` l, millimeter), for the range. R at whichthe ,instrument is.intended to operate.

Fonexample, if the mirrordistance m=20k centimeters andthe focallengthofthe deflecting lenses fzO meters, thev displacement c. necessary for,settingon an objectv atl In Fig, 2, these deiectingtmembers` are.

lenses. indicatedvbyE, E. and E2, E being used for ydistances frominfinity to 10,000 i meters, for distancesl from infinity to 1,000meters and E2 for distances froininfinityto 100 meters. The, focallengths are,

respectively, 40 meters, 1 meters. and; 40`

centimeters, and,.thedispla cement of cach at the distances mentioned is.8 millimeters. inprderytdpermit the use of each defiectingmeinbensepaijately, thel others must be.

moved into an inoperative position. -In the presentinstance, each ofthelenses E, E

and E2 isv` adjacent a, complementary lens indicated ,by E? andY E?,respectively, and

th'lenses of each pair when alined optically.`

neutralize ,eachptherand no` bending or .defleeieaeiaihe 1ere eeeule.Tllereferefwhea Lamme making a reading by adjusting a member of onepair, the lenses'of `the other pairs are alined optically with the.telescope, and do not have any effect in delecting the ray B. j Thelenses E, E and E2 are each carried in slides 6 movable transversely ofthe axis of the telescope in guideways formed in blocks 7, secured injuxtaposition by plates 8, fastened at opposite ends of the blocksy byscrews 9, the extreme blocks being provided with cylindrical reducedportions lll@ upon which fit the two opposite portions of the tube 3.The lenses F, F and F2 are carried by the blocks 7 adjacent the lensesE, E and E2. Each of the slides 6 is moved longitudinally by means of ascrew 9 journaled in one of the plates 8 and threaded within the slide.A projection 10 on the slide extends through a slot 11 in the block andcooperates with divisions of a scale D to indicate the distance of theobject viewed, the subdivisions. being read from graduations on acylindrical portion 12 on the screw cooperating with an index 12a on theblock 7 Springs 13 interposed between one of the plates 8 and the` slide6 serve to prevent lost motion of the latter.

In Fig. 7 I have shown a modified structure for use as a gun-sight inwhich the tube 18 extends vertically and the telescope 19 is disposed atright angles thereto. The rays A in this case pass through the mirror 1while the rays B are reflected thereby, as shown in Fig. 8. The rangefinder is carried on the gun barrel and is movable angularly thereto byadjusting means movable with the deflecting means, whereby the gun willbe given the proper trajectory when the images are in coincidence. Inthe present instance the range finder is pivoted at 20 to a bracket 21on the gun barrel 22, and is moved relatively thereto by means of a cam23, moved in unison with the screw 9 by means of a pinion 211 meshingwith a gear on the cam, said cani engaging a roller, or abutment 26 onan extension 27 of the bracket 21. In sighting an object the gun iselevated as the screw 9 is adjusted, the cam being so designed as togive the proper angle of elevation of the gun for every distance. Ayielding connection is provided for the purpose of preventing the recoilof the gun from injuring the instrument, said connection consisting' ofa spring 28 engaging the mstrument and gun at its opposite ends as at 29and 30, and normally acting to keep the cam 23 in. Contact with theroller 26.

1When the gun is fired the recoil moves the pivot 20 rearwardly, and theinertia of the instrument causes it to rock forwardly against thetension of the spring 18, the cam 23 moving out of contact with theroller 26. A dash pot consisting of a cylinder 31 on the gun and apiston 32 operating therein and connected to the tube 19 allows theinstrument to move freely in this direction, but prevents j arring whent'ne spring 28 returns the cam 23 into contact with the roller 26.

I claim as my invention:

1. In a range finder, the combination with means for directing one oftwo sets of rays of light emanating from an object at an angle to eachother 1n the same general direction as the other set to produce twoimages viewable from the same point of observation, of a plurality ofdeflecting members of relatively different power for selectively bendingthe rays of one image into coincidence with those of the other to causethe images to register, and means for operating one deflecting member toa neutral position while another is in use.

2. In a range finder, the combination with a pair of reflectors fordirecting rays of light from an object into position to enable anobserver to see two separate images thereof, of a plurality of deiectingmembers of different power independently movable in the path of the raysof one image for bending the rays and causing coincidence of the images,and indicating means movable with each of the deieeting members todetermine the distance of the object when the images are in coincidence.

3. In a range finder, the combination with means for directing one oftwo sets of rays of light emanating from an object at an angle to eachother in the same general direction as the other set to produce twoimages viewable from the same oint of observation, of a plurality of deecting members of relatively different power for selectively bending therays of one image into coincidence with those of the other to cause theimages to register, each deflecting member being movable to a neutralposition in the path of the rays.

4. In a range finder, the combination with means for directing one oftwo sets of rays of light emanating from an object at an angle to eachother in the same general direction as the other set to produce twoimages viewable from the same point of observation,

of a plurality of deflecting members of rela- A tively different powerfor selectively bending the rays of one image into coincidence withthose of the other to cause the images to register, each deflectingmember comprising a pair of complementary lenses of the same focallength, one of which is movable relatively to the other in a directionlaterally of their common axis.

5. In a range finder, the combination with a pair of reflectors fordirecting rays of light from an object into position to enable anobserver to see two separate images of the object, and a telescope formagnifying the images, of a plurality of pairs of lenses of lllidifferent focal lengths arranged inthe path of the rays toone-reflector, each pair consi'stingv of a convex and concave-lensarranged With their optical axes normally in alinelnent With that of thetelescope,vone lens of each pair being fixed and the other movablelaterally of the axis of f the telescope, independent adjusting meansfor displacing each' of the movable lenses across the path of CopiesAof-thispatenc may be obtained for the rays to cause coincidence of theimages, and indicators operated by each of the adjusting means todetermine the distance of the object when the images are in coincivecents each, by addressing the Commissioner of Patents, Washington, D. C.

